Chains are well known in the art and are normally classified by use. Roller chains are used, for example, to drive a sprocket. In this type of chain, tension forces are applied along the length of the chain. Normally no forces are applied perpendicular to the path of travel of the chain.
Another type of chain is an engineering class steel chain. While roller chain primarily meet drive chain needs, engineering steel chains are often used where designed for difficult conveying applications. The present invention is directed to an engineering class steel chain which is used to convey, for examples, truck or automobile components in a factory operation. The vehicles are placed on custom designed pallets which are normally carried along the upper surface of the engineering steel conveyor chain. The weight of the vehicles places a downward compression load on the upper surface of the conveyor chain.
The conveyor chains include side bars and rotating steel rollers which support the pallets. Normally pins extend between the side bars of the conveyor chain and rollers are mounted for rotation on the bushing pin. It has been found that as the chains wear, the friction and loading of the chains tend to restrict rotation of the rollers. To alleviate this problem, it is common to lubricate the rollers with various types of lubricating oils or greases. The wear, maintenance and cleaning of prior art chains create problems for the users. In addition to the inherent problems with the use of solvents, the overall waste problems and wear problems are significant.
The present invention is directed to an improved engineered steel chain, for carrying loads perpendicular to the path of chain movement.